This disclosure is generally directed to imaging, such as xerographic imaging and printing members, photoreceptors, photoconductors, and the like. More specifically, the present disclosure is directed to drum, multilayered drum, and flexible, belt imaging members, or devices comprised of a supporting medium like a substrate, a photogenerating layer, and a charge transport layer, including a plurality of charge transport layers, such as a first charge transport layer and a second charge transport layer, and wherein at least one of the photogenerating layer and charge transport layer contains as an additive or dopant a ferrocene, and a photoconductor comprised of a supporting medium like a substrate, a ferrocene containing photogenerating layer, and a ferrocene containing charge transport layer that results in photoconductors with a number of advantages, such as in embodiments, minimal charge deficient spots (CDS); the minimization or substantial elimination of undesirable ghosting on developed images, such as xerographic images, including acceptable ghosting at various relative humidities; excellent cyclic and stable electrical properties; compatibility with the photogenerating and charge transport resin binders; and acceptable lateral charge migration (LCM) characteristics, such as for example, excellent LCM resistance and on line control, and adjustment of the photoconductor photosensitivity. At least one in embodiments refers, for example, to one, to from 1 to about 10, to from 2 to about 6; to from 2 to about 4; 2, and the like.
Also included within the scope of the present disclosure are methods of imaging and printing with the photoconductor devices illustrated herein. These methods generally involve the formation of an electrostatic latent image on the imaging member, followed by developing the image with a toner composition comprised, for example, of thermoplastic resin, colorant such as pigment, charge additive, and surface additives, reference U.S. Pat. Nos. 4,560,635; 4,298,697 and 4,338,390, the disclosures of which are totally incorporated herein by reference, subsequently transferring the image to a suitable substrate, and permanently affixing the image thereto. In those environments wherein the device is to be used in a printing mode, the imaging method involves the same operation with the exception that exposure can be accomplished with a laser device or image bar. More specifically, the imaging members and flexible belts disclosed herein can be selected for the Xerox Corporation iGEN3® machines that generate with some versions over 100 copies per minute. Processes of imaging, especially xerographic imaging and printing, including digital, and/or color printing are thus encompassed by the present disclosure.
The photoconductors disclosed herein are in embodiments sensitive in the wavelength region of, for example, from about 400 to about 900 nanometers, and in particular from about 650 to about 850 nanometers, thus diode lasers can be selected as the light source. Moreover, the photoconductors disclosed herein are in embodiments useful in high resolution color xerographic applications, particularly high-speed color copying and printing processes.
In embodiments, the ferrocene additive is dissolved in the photogenerating solvent, such as tetrahydrofuran, and subsequently the resulting mixture can be added to the appropriate photoconductor layer, such as the photogenerating layer, on line with simple mixing since the additive is soluble in THF, thereby tuning the PIDC, that is, adjusting the PIDC slower when a fast or rapid PIDC is observed on line. Similarly, the ferrocene additive is dissolved in the (SMTL) solvent, such as methylene chloride, and can be readily added into the SMTL solution, especially the first pass SMTL solution, on line with simple mixing since the additive is soluble in solvents like methylene chloride, permitting tuning the PIDC, that is, adjusting the PIDC slower when a fast or rapid PIDC is observed on line. For example, the ferrocene included in the photogenerating layer resulted in an about 30 volt change in the PIDC, and similarly with the ferrocene containing charge transport layer the change in PIDC was about 40 volts.
The ferrocene additive or dopant, which can be incorporated into the photogenerating layer, and which dopant functions, for example, to passivate the photogenerating pigment surface by, for example, blocking or substantially blocking intrinsic free carriers, and preventing or minimizing external free carriers from attracting to the pigment surface, and thereby permitting photoconductors with minimal CDS (charge deficient spots), the control of PIDC, for example controlling, and more specifically, slowing the PIDC, especially in those situations where the photosensitivity of the photoconductor can be adjusted on line and automatically, to a desired preselected value or amount, and which photosensitivity can be increased or decreased; and acceptable LCM characteristics, such as for example, acceptable lateral charge migration (LCM) resistance. Similarly, the ferrocene additive can be incorporated into the charge transport layer, and in embodiments there can be accomplished the on line and automatic addition of the ferrocene to this layer.